In early 2017, Ismaele La Vardera, a 22-year-old Sicilian journalist, surprised the Italian political scene when he announced his candidacy for mayor in the southern city of Palermo. Even more surprising was his decision to stand for the League, whose leader, Italy’s interior minister, Matteo Salvini, has repeatedly denigrated southern Italians.

On election night on 12 June La Vardera secured just 2.7% of the vote. But there was a twist in the tale: he had taken a hidden camera with him on the campaign trail, and recorded his experience.

The footage has been made into a documentary called Italian Politics for Dummies. Scheduled for release at the end of November, the film shines a light on the workings of Italy’s populist parties, as well as alleged mafia interference.

“While I was on the campaign trail, I was amazed by certain things that were happening to me,” La Vardera said in an interview. “That’s when I decided it might be worth it to record everything.”

La Vardera styled himself as a David battling the Goliaths of the political establishment. He was immediately courted by Salvini’s party, who were interested in marketing him as an anti-establishment outsider. Salvini formalised the party’s endorsement during a two-hour conversation with La Vardera that was secretly filmed. He told the young candidate the party would present him as “something totally new in the swamp of old politics”.

La Vardera was also courted by Giorgia Meloni, the leader of the far-right party Fratelli d’Italia, who offered to put him on the party slate.

The most striking segment of the film takes place in the basement of an apartment building in the Kalsa neighbourhood of Palermo, a Sicilian mafia stronghold. La Vardera had been accompanied to the apartment by a former Palermo councilman to meet a relative of the imprisoned mafia boss Gino “U Mitra” Abbate.

The relative offered a deal: “We can deliver 300 votes in this district, but they’ll cost you €30 (£26) each. Here, people need food. Here, we decide who people will vote for, otherwise they don’t vote.”

“I was astonished,” La Vardera said after. “I thought, is this really happening to me?” As for his League endorsement, La Vardera said the party would never have found out about the deal. “Anyone who makes a deal with a boss doesn’t talk about it,” he said.

In another scene from the film, La Vardera is invited to the home of the former Sicilian governor Salvatore Cuffaro, who served nearly five years in prison for aiding the Cosa Nostra. In the event of a second ballot, Cuffaro tried to convince him to support the candidate running for mayor with another party, Forza Italia.

In exchange, Cuffaro suggested he could work out a position for La Vardera in local government or “in a coalition during the next round of Italian elections”. “If you play with us, I will do what it takes so that you’ll be elected,” Cuffaro said. The implication, La Vardera said, was that despite his criminal conviction, Cuffaro was acting as political matchmaker.

When La Vardera went public after the election and admitted to having recorded his meetings on hidden camera, a frenzied debated ensued around the ethics of his work. Had he offered a fake candidacy with the sole purpose of making a film? A judge has since ruled that his campaign was authentic.

After the vote the journalist went back to the people he had secretly filmed, including Cuffaro and Meloni. “There are already tons of wiretaps about me in court,” Cuffaro joked. “The conversations you have recorded between me and you, will not change anything’’.

Meloni, who had publicly endorsed La Vardera, said she was “disappointed with him”. “If you are trying to prove we all suck then do it,” Meloni told him. She said she would not pursue him in the courts. Salvini declined to comment.

Davide Parenti, one of the most famous television producers in Italy, co-produced the film. He said he hoped it would shed light on the workings of Italian politics. “The logic of the old system was ‘I scratch your back, you scratch mine,’” Parenti said. “Today’s politicians in Italy work toward immediate consensus,” he added, referring to the advances made by the League and Fratelli d’Italia towards La Vardera.

The irony, Parenti said, is that for Italy’s populists, “everything is live and measurable by social media, as if no action makes sense unless it’s recorded by someone. Who knows how they’ll react to the fact that we recorded everything? Even them.”